High-pressure boiler



D. s. JAcoBus HIGH PRESSURE BOILER June 18, 1929.

I 2 Sheets-Sheet Filed June 50, 1926 June 18, 1929. D, 5, JACVOBUS 1,718,048

HIGH PRESSURE BOILER Filed June 30, 1926 2 Sheets-Sheet 2 Z INVENTQR I BY v I I ,Jwfi: "f4 j w ATTORNEYS Patented 18, 1929.

UNITED STATES 1, 11ao'4s PATENT OFFICE.

DAVID S. JACOBUS, OF MONTCLAIR, NEW JERSEY, ASSIGNOR TO THE BABCOGK & WIL- GOX. COMPANY, OF BAYONNE, NEW JERSEY, A CORPORATION OF NEW JERSEY.

HIGH-PRESSURE BOILER.

Application filed June so,

This invention relates to a high pressure steam boiler of the Stirling type, and will be understood from the description in connection with the accompanying drawings, in

which Fig. 1 is a vertical section through an illustrative embodiment of the invention; Fig. 2 is a section on an enlarged scale through one of the drums, partly broken away; Fig. 3 is a sectionalong the line 33 of Fig. 2; Fig. 4 is a section similar to Fig. 2 on a still larger scale and Fig. 5 is a sectionsimilar to Fig. 4, showing a modification.

The invention will be specifically described in connection with a Stirling type of boiler,

in which the drums have very thick walls and the tubes extend into the drums without extending through the walls thereof, but it is to be understood that the invention is not restricted to boilers of this particular type.

In the drawings, reference character 10 indicates the lower or mud drum of the boiler, and reference characters 11 and 12 indicate the upper drums of the same, these drums being connected to each other by banks of tubes 13, 14 and 15, the tubes being bent near their ends so that they will enter the drums radially. It will be seen that the ends of the tubes are brought close together where they enter the drums, and that the width of the tube bank .3 is greater than the chord subtended by'the portion of drum circumference which is occupied by the tube holes for the bank. Baflles 16, 17, 18, 19 and 20 are provided to direct the hot products of combustion over and along the tubes from the furnace, which may be located beneath the boiler, to the outlet 21 for the waste products of combustion.

It will be seen by referring particularly to Figs. 2 and 4 of the drawings, in which the. drum 11 is shown in section partly broken away, that holes for the tubes extend through the walls or shells of the drums perpendicular to, the surfaces of the drums. or in radial directions from the axes of the drums. The first 45 portion'22 of the tube holes extends from the outside surface of the drum inwardly a sufficient distance to provide a flange forming a tube seat, and one or more annular recesses 23' I may be provided in this portion to aid in keeping .the tubes in place in the tube seats. Inwardly of the portion 22 the holes are counterboard, as indicated at 24 and 25. The

part 24 is connectedto the seat by a broad radially extending shoulder and is made with parallel cylindrical walls, while the part25 1921;. Serial in. name.

has walls tapering inwardly toward the in side of the drum. The portlon 26 of the hole, in the form of a flange between the end of the counterbored part 25 and the inside surface of the drum is made of smaller diameter than the portion 22, so as to leave a larger amount of metal, thus providing greater ligament strength for the drum.

The above construction results in the formation of a ligament between adjacent holes of the form best shown in Figs. 2 and 4. By the term ligament, I refer to the metal in a plane passing through the axes of two adj acent holes, the cross-sectional area of this metal being measured at the point where the two holes "are nearest each other. By making the ligaments between adjacent holes with their longest dimensions lengthwise of the holes or lengthwise of the tubes, and making the distance between adjacent holes relatively small with respect to the thickness of the wall, and with the special form of hole shown, I provide the necessary ligament strength and yet make it possible to space the tubes closely together at the points where they enter the drum.

The tubes 13 extend'through the portion 22 of the holes and are expanded into contact therewith, having'their ends flared into the counterbored part 24, as shown at 27.

In order to prevent the drums from being blistered'or burned out by radiant heat or by impinging of hot gases against the same, a protecting cover of heat-insulating material, made of plastic fire-brick, for example, may

be installed next to the drums. This protecting cover may be held in place by means of U-b'olt clips 28 on some of the tubes that retain curved straps 29. Cross ieces 80 are held behind the straps 29 exten ing between rows of tubes 13, and serve to retain the covering 31 of heat-insulating material in place. The edges of these cross pieces 30 may, if desired, be provided with notches to enable wider gross pieces to be inserted between the tubes In the modification shown in Fig. 5, the

tube seat portion 22' is provided with an annular groove 23', the counterbored portion 24 is of sufficient size to enable the end of the tube 13 to be flared outwardly, as shown at 27 and the smaller portion 26' of the hole is made of uniform diameter.

By providing holes into which the ends of the tubes can be ex anded and seated without passing entirely t rough the walls of the drums,the tubes can be readily installed and replaced without. requiring the tubes to be sprung or bent any considerable amount. In order to insert a tube one end is first passed through a tube hole in one of the drums a sufficient distance to bring the opposite end of thetube opposite the tube hole in the other drum, after which the tube is removed. a sufficient distance from the tube hole in which it is first inserted to make it come to its final position in the boiler and the proper position for being expanded at its twoends. In order to make it possible to install the tubes in this way', those'portions of the tube holes which are made larger than the holes in the tube seats must extend asuflicient distance beyond the tube seats. Theportions of the tubes which come beyond the bends at the ends of the tubes are straight for a sufficient distance and the tubes are made of such a length and the thickness of the tube seats so proportioned as to make possible this method of installing the tubes. By having the interior ends of the holes of smaller diameter than the portions into which the tubes extend, the'drums are left with greater strength than would be the case if the holes of the size of the tubes extended entirely through the drum shells. By terminating the tubes short of the inside of the drums, the water in the boiler will come in direct contact with the metal of the drums in passing through the holes leading to the tube ends, thus aiding in keeping the drums cool. By bringing the water in direct contact with the metal of the drums for a large portion of the surfaces of the holes, better cooling action can be secured than by passing the tubes completely'through the shells of the drums. By applying a layer of heat-insulating material or a protecting coverin on the drums, the danger of burnlng or over eating the same is obviated.

The counterbored portions of the tube holes are formed-with fillets in order to avoid the localized stresses which wouldcome through the presenceof a sharp corner.

I claim"! 1. A water tube steam boiler comprising a drum provided with a relatively thick wall, a plurality of tubes secured in holes in the wall of said drum, each hole being provided with an inwardly extending flange adjacent the outer surface of said wall and forming the tube seat, a second flange adjacent the inner surface of said wall, and an intermediate portion of relatively large-diameter extend- 1 mg beyond the end of said tube and within which the said end is disposed.

2., A water tube steam boiler comprising a drum provided with a relatively thick wall, a plurality of tubes secured-in holes in the wall of said drum, each hole being provided with an inwardly extending flange adjacent the outer surface of said wall and forming the tube seat, a second flange adjacent the inner surface of said wall, and an intermediate portion of relatively large diameter within which the end of said tube is disposed, said relatively large portion being formed of two parts, one with substantially parallel walls and the other with tapered walls.

3. A- water tube steam boiler comprising a drum having a relatively thick wall with a hole therethrough, said hole being enlarged intermediate its ends to provide a tube seatof less depth than the thickness of the wall, and to provide a space inwardly of said seat of larger diameter than the seat and-of suf-' the wall thickness and of larger diameterthan said seat and disposed inwardly thereof and of suflicient depth to permit the end of the tube to be passed a suificient distance beyond the seat to bring the opposite end of the tube opposite a seat in another drum, after which the said other end may be made to enter said other drum, and the tube brought to its final position in the boiler and in correct position to be expanded into said seats, said hole terminating at'its inner end in a portion having a diameter no larger than that of the sea 5. In a water tube steam boiler a drum havin g a relatively thick wall with a hole therethrough, said hole having a tube seat of less depth than the thickness of the wall and disposed adjacent the outer surface thereof, a concentric counterbore in said hole disposed inwardly of said tube seat and of a larger diameter than the tube seat, said counterbore having a depth that will allow the tube to be advanced beyond the final position it occupies in the boiler, said hole adjacent the inner surface of the Wall having a smaller diameter than that of the counterbore.

6. A water tube steam boiler comprising a.

drum provided with a relatively thick wall having a hole therethrough, said hole having aplurality of flanges extending inwardly from the perimeter thereof, and a tube seated on one of said flanges and .out of contact with the others.

7. A water tubesteam boiler comprising a therebetween, and a tube seated on one of said flanges and out of contact with the other.

8. A Water tube steam boiler comprising a drum provided with a relatively thick wall I counterbore and out of contact with said inner flange.

9. In a heat transfer device, a pair of high pressure receptacles connected by tubes, at least some of said tubes having their ends bent to enter holes in the walls of said receptacles, one of the receptacles having a diameter such as to require a wall thickness much greater thanthe length of tube seat, each hole being enlarged intermediate its ends to provide a tube seat in the outer portion of the hole, and

to provide a space inwardly of said seat of sufiicient length to allow bringing the other end of the tube into registry with the tube seat in the other receptacle, without injurious springing or bending of said tube.

10. In a heat transfer device, a pair of high pressure receptacles connected by tubes, one

of said receptacles having a diameter such as to require a wall thickness much greater than the necessary length of tube seat, such Wall having a through hole with the tube seat in the outer portion for each tube and with an enlarged portion terminating at points intermediate of the wall thickness, the enlarged portion being of suflicient length to allow bringing the other end of the tube into registr with the tube seat in the other receptacle without injurious springing or bending of said tube, the inner end portion of the hole being smaller than the tube seat portion.

11. In a heat transfer device, a pair of high pressure receptacles connected by tubes, one of said receptacles having a diameter such as to require a wall thickness much greater than the necessary length of tube seat, such wall having a through hole with a tube seat in its outer portion and with an enlarged portion joined to the tube seat by a radially extending shoulder forming the end of the tube seat, the inner ortion of the hole being not larger than the intermediate enlarged portion, the ligaments at the inner ends of the holes containing substantially as much metal as those at the outer ends thereof.

12. In a heat transfer device, a high pressure cylindrical drum havingtubes entering holes in the wall thereof, said drum being of such a size as to requirea wall thickness greater than the necessary length of tube seat, two adjacent tube holes being separated by a ligament which is relatively narrow with respect to the thickness of the wall and to the diameter of the tubes, the ends ofsaid ligament being of greater widths than its middle portion. 13. In a heat transfer device, a high pressure receptacle having tubesentering holes in a wall thereof, said receptacle being of such a size as to require a wall thickness much greater than the necessary length of tube seat,

two adjacent holes being separated by a ligament which is relatively narrow with respect to the thickness of the wall and to the diameter of the tubes and has a wider portion adjacent the outer surface of the wall forming a tube seat, and a second wider portion adjacent the inner surface of the wall.

14. In a heat transfer device, a high pressure cylindrical drum having tubes enteringradially extending holes in the wall thereof, said. drum being of such a size as to require a wall thickness greater than the necessary length of tube seat, said tubes being disposed in a bank of greater width than the chord subtended by the portion of drum circumference occupied by the tube holes, the tubes being curbed at their ends to enter said holes substantially radially of the drum, said holes having tube seats adjacent the outer surface of the wall and being'separated by ligaments having their longest dimensions lengthwise of the holes, and having their ends which are adjacent the inner surface of the wall of a greater width than the minimum width of the ligaments.

15. In a heat transfer device, a high pressure cylindrical drum having tubes entering radially extending holes in the wall thereof, said drum being of such a size as to require a wall thickness greater than the necessary length of tube seat, said tubes being disposed in a bank of greater width than the chord subtended by the 1portion of drum circumference occupied by t e tube holes, the tubes being curved at their ends to enter said holes substantially radially ,of the drum, said holes having tube seats adjacent the outer surface of the wall and being separated by ligaments theret rough, said hole having a tube seat of less depth than the thickness of the wall and disposed adjacent the outer surface thereof, a concentric counterbore in said hole disposed inwardly of said tube seat and of a'larg er diameter than the tube seat, said counterbore, having a depth that will allow the tube to be advanced beyond the final position it occupies in the boiler, said hole adjacent the inner surface of the wall having a smaller diameter than that of the tube seat.

17. In a water tube steam boiler a drum havin a relatively thick wall with a hole theret rough, said hole having a tube seat of less depth than the thickness of the wall and disposed adjacent the outer surface thereof, a concentric counterbore in said hole disposed inwardly of said tube seat and of a larger diameter than the tube seat, said counterbore having a depth that will allow the tube to be advanced beyond the final position it occupies in the boiler, said hole adjacent the inner surface of the Wall having a diameter substantially equal to the inside diameter of the tube.

18. In a water tube steam boiler a drum having a relatively thick wall with a hole therethrough, said hole having a tube seat of less depth than the thickness of the wall and disposed adjacent the outer surface thereof, a concentric counterbore in'said hole disposed inwardly of said tube seat and of a larger diameter than the tube seat, said counterbore having a depth that will allow the tube to be advanced beyond the final position it occupies in the boiler,- said hole adjacent the inner surface. of the wall having a diameter smaller than the inside diameter of the flared end of a tube expanded into position on said seat.

19. In a heat transfer device, a high pressure cylindrical drum having tubes entering radially extending holes in the wall thereof, said holes having enlarged counterbores disposed intermediate the thickness of the wall and being separated by ligaments having tube seats adjacent the outer surface of the wall, the thickness of the ligament adjacent the inner surface of the wall being greater than it would be if the tube seat were prolonged inwardly for the full thickness of the wall, the end of each tube being disposed in the counterbore and out of contact with the inner end 

